This invention relates to multiple cycle liquid treatment apparatus and more particularly to an improved flow control valve that automatically starts and stops the different cycles.
Water softening apparatus using ion exchange resin particles must be regularly regenerated with brine in order to restore or maintain the water hardness removing capacity of the resin particles. The flow control valve for such apparatus must accurately control the volume and velocity of liquid flowing through the resin particles and the brining system during four or more cycles. Automatic water softening apparatus used in people's homes has to be capable of operating under a wide range of pressure, flow, and hardness conditions. Prior flow control valves usable under such a wide range of conditions were often unduly complicated and difficult to service because they had a large number of moving parts. Also, such prior valves were not capable of being used with different types of liquid treatment equipment, such as filters, requiring high flow rates during their backwash cycle.